/*
 * Copyright 2020-2030 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.wwl.usecase;

/**
 * @author Neil Wang
 * @version 1.0.0
 * @date 2021/6/10 4:09 下午
 */
public class ListNode {
    int val;
    ListNode next;

    public ListNode(int[] arr) {
        if (arr == null || arr.length == 0) throw new IllegalArgumentException("arr can not be empty.");
        this.val = arr[0];
        ListNode cur = this;
        for (int i : arr) {
            cur.next = new ListNode(i);
            cur = cur.next;
        }
    }

    public ListNode(int x) {
        val = x;
    }

    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder();
        ListNode cur = this;
        while (cur != null) {
            sb.append(cur.val).append("->");
            cur = cur.next;
        }
        sb.append("NULL");
        return sb.toString();
    }
}
